1,2,3,4 King George’s Medical University, UP, Lucknow, India 226003
5,6 Atal Bihari Vajpayee Medical University, UP, Lucknow, India 226003
Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide, especially in hospitalized patients with comorbidities. Understanding prescription patterns and treatment outcomes is critical for improving care and promoting antimicrobial stewardship. To evaluate prescription patterns, therapeutic outcomes, and adverse drug reactions (ADRs) in CAP patients admitted to a tertiary care hospital, and to assess the impact of physician-related factors on prescribing behavior. A prospective observational study was conducted among 300 CAP patients admitted to a tertiary care hospital. Sociodemographic, clinical, laboratory, and radiological data were collected. Prescriptions were analyzed for antibiotic choice, adjunct therapies, and guideline adherence. Patients were followed for regimen modifications, ICU admission, need for ventilation, hospital stay, and mortality. ADRs were recorded and classified. Data were analyzed using Chi-square tests, t-tests, ANOVA, and logistic regression. The mean patient age was 54.2 years; 63% were male. Most patients (61.3%) belonged to lower socioeconomic groups, and 64% presented with severe/very severe CAP. Ceftriaxone + azithromycin (43.3%) was the most common regimen, followed by cefoperazone–sulbactam + levofloxacin (21%). Empirical therapy predominated (95%), with targeted therapy in 5%. Regimen modifications occurred in 26%. ICU admission was required in 32%, mechanical ventilation in 16.7%, and in-hospital mortality was 4%. Guideline-adherent therapy was associated with shorter hospital stay (5.4 vs. 7.2 days) and better outcomes. ADRs occurred in 7.3%, mostly mild gastrointestinal or dermatological events. Empirical prescribing remains predominant in CAP, but adherence to guidelines improves outcomes and reduces mortality. Strengthening diagnostic integration, antimicrobial stewardship, and prescriber training is essential in tertiary care settings.
Community-acquired pneumonia (CAP) is one of the most common and serious infectious diseases worldwide, contributing significantly to morbidity, mortality, and healthcare burden (WHO 2020; Jain et al. 2015; GBD 2017). It is defined as an acute infection of the pulmonary parenchyma acquired outside of healthcare settings and is characterized by cough, fever, pleuritic chest pain, dyspnea, and new radiographic infiltrates (Mandell et al. 2007; Metlay et al. 2019; Torres et al. 2021). Among pathogens, Streptococcus pneumoniae remains the most frequent cause globally, though atypical bacteria such as Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and respiratory viruses including influenza and SARS-CoV-2 are also implicated (Musher & Thorner 2014; Cilloniz et al. 2016; Jain et al. 2015; Torres et al. 2021).
The global burden of CAP is substantial, accounting for nearly 6% of all deaths and ranking among the top 10 causes of mortality (GBD 2017; WHO 2020; Gutiérrez et al. 2020). Mortality is particularly high in elderly populations, immunocompromised individuals, and those with underlying comorbidities (Prina, Ranzani & Torres 2015; Cilloniz et al. 2016; Torres et al. 2021). In India, CAP represents a major public health issue, with hospital-based studies showing high case fatality rates in patients with diabetes, COPD, and cardiovascular disease (Mohan et al. 2017; Chawla et al. 2018; Singanayagam et al. 2013). The socioeconomic burden is compounded by long hospital stays, high antimicrobial costs, and indirect economic losses (Laxminarayan et al. 2013; Rajasurya et al. 2018).
Risk factors for CAP are multifactorial, spanning demographic, lifestyle, and clinical domains. Advanced age, smoking, alcohol misuse, malnutrition, and exposure to poor air quality or biomass fuel are well-recognized contributors (Marrie 2010; Millett et al. 2013; GBD 2017). Chronic comorbid conditions such as diabetes, COPD, chronic kidney disease, heart failure, and immunosuppressive therapy significantly elevate susceptibility and worsen prognosis (Prina et al. 2015; Torres et al. 2021; Chalmers et al. 2016).
The pathophysiology of CAP involves pathogen invasion of the lower respiratory tract, activation of host inflammatory cascades, neutrophil influx, and alveolar exudate accumulation. This cascade disrupts pulmonary gas exchange, leading to hypoxemia and systemic complications such as sepsis and multi-organ dysfunction (Cilloniz et al. 2016; Musher & Thorner 2014; Torres et al. 2019). Dysregulated immune responses are particularly detrimental in severe CAP, where cytokine storm-like mechanisms contribute to lung injury (Hajj et al. 2021; Bordon et al. 2013).
Antibiotics remain the cornerstone of CAP management. Empirical regimens typically include beta-lactams, macrolides, or fluoroquinolones, either as monotherapy or in combination depending on severity (Mandell et al. 2007; Metlay et al. 2019; Torres et al. 2021). However, the irrational or excessive use of antibiotics is a pressing issue, driving antimicrobial resistance (AMR)—a phenomenon disproportionately affecting low- and middle-income countries (Laxminarayan et al. 2013; Goossens et al. 2005; Klein et al. 2018). In India, AMR rates for pneumococci and Klebsiella pneumoniae are alarmingly high, complicating treatment strategies (Chawla et al. 2018; WHO 2020).
In addition to antibiotics, non-antibiotic therapies are used to alleviate symptoms or modulate inflammation. Corticosteroids, mucolytics, bronchodilators, and antipyretics are common adjuncts; however, the role of corticosteroids in severe CAP remains controversial, with mixed evidence regarding mortality benefit and risk of adverse effects (Siemieniuk et al. 2015; Stern et al. 2017; Torres et al. 2015). Supportive measures such as intravenous fluids, oxygen therapy, and mechanical ventilation are often required in severe or ICU-managed cases (Restrepo et al. 2008; Rello et al. 2017).
Despite advances in diagnostics, timely and accurate identification of CAP remains challenging. Conventional chest radiographs, while widely used, have limited sensitivity and specificity (Metlay et al. 2019; Claessens et al. 2015). Molecular diagnostic methods such as PCR and multiplex respiratory panels offer improved accuracy but are less accessible in resource-constrained healthcare settings (Torres et al. 2021; Jain et al. 2015). Biomarkers such as procalcitonin and CRP are increasingly utilized to guide antibiotic stewardship, though their predictive utility remains debated (Schuetz et al. 2017; Self et al. 2017).
In summary, CAP continues to pose major challenges due to diagnostic complexities, rising AMR, and variability in prescribing practices across healthcare systems (GBD 2017; WHO 2020; Torres et al. 2021). Rational prescribing, antimicrobial stewardship, and evidence-based use of adjunctive therapies are critical for improving outcomes. Further research into prescription patterns, therapeutic outcomes, and adverse drug reactions is essential to optimize CAP management and reduce its global burden (Metlay et al. 2019; Chalmers et al. 2016).
The present study aims to evaluate the prescription patterns, therapeutic outcomes, and adverse drug reactions in patients admitted with CAP to a tertiary care hospital. Specifically, it will analyze the use of antibiotics, non-antibiotic drugs, and supportive therapies, correlate prescription trends with clinical status and outcomes, and assess the impact of ADRs on patient management.
METHODOLOGY
Study Design and Site
This prospective observational study was conducted at King George’s Medical University (KGMU), Lucknow, in collaboration with the Departments of Pharmacology and Department of Medicine and Pulmonary Medicine.
Study Population and Sample Size
Patients diagnosed with community-acquired pneumonia (CAP) admitted to the wards and ICUs of Medicine and Pulmonary Medicine at KGMU were enrolled. Based on a reported 26.1% inadequacy of empirical antibiotic use, the sample size was calculated using the formula n ≥ Z²p(1–p)/d² with 5% precision, yielding 300. After a 5% contingency, the final sample size was set at 315 patients.
Inclusion Criteria
Exclusion Criteria
Ethical Considerations
Approval was obtained from the Institutional Ethics Committee, and informed consent was taken from all participants or their legal guardians.
Study Procedure
Eligible patients were enrolled after consent. Data on socio-demographics, medical history, co morbidities, and risk factors (smoking, alcohol, tobacco use) were recorded. Clinical, hematological, biochemical, and arterial blood gas investigations were performed. Sputum Gram stains and culture were carried out to identify pathogens.
Severity of CAP was categorized as mild/moderate, severe, or very severe. Prescriptions at admission were documented, including:
Details of the treating physician-in-charge, including age, qualifications, and years of experience, were also noted.
Patients were followed throughout hospitalization, and changes in prescriptions, additional interventions, and adverse drug reactions (ADRs) were recorded. The clinical course was monitored, and outcomes included:
Treatment adequacy was assessed against Joint JCS/NCCP(T) guidelines for CAP management.
Data Analysis
Data were analyzed using IBM SPSS Statistics version 21.0. Prescription adequacy, antibiotic use, prescription changes, ADRs, and intervention needs were compared against disease severity, patient outcomes, and physician-related factors (age, qualification, experience). Statistical tests included Chi-square test, independent samples t-test, and ANOVA.
Results
Baseline Characteristics
A total of 300 patients with community-acquired pneumonia (CAP) were enrolled (Table 1). The mean age was 54.2 years (range: 18–87), with a male predominance (63.0%). Most patients belonged to the lower socioeconomic group (61.3%) and had limited educational attainment (Table 2).
Table 1: Age and Gender Distribution of Patients (N = 300)
|
Age Group (years) |
Male (n = 189) |
Female (n = 111) |
Total (%) |
|
18–30 |
21 |
18 |
13.0% |
|
31–50 |
48 |
27 |
25.0% |
|
51–70 |
81 |
47 |
42.7% |
|
71–87 |
39 |
19 |
19.3% |
Table 2 Socioeconomic and Educational Background of Patients
|
Category |
Frequency |
Percentage |
|
Socioeconomic Status – Lower |
184 |
61.3% |
|
Socioeconomic Status – Middle |
92 |
30.7% |
|
Socioeconomic Status – Upper |
24 |
8.0% |
|
Educational Status – Illiterate |
110 |
36.7% |
|
Educational Status – Primary |
96 |
32.0% |
|
Educational Status – Higher Secondary & Above |
35 |
11.7% |
Clinical Profile and Co morbidities
The majority presented with cough, fever, and dyspnea, while altered sensorium was seen in older patients. Co morbidities were present in 66%, with COPD, diabetes, and hypertension being most frequent. Results are illustrated in Figures 1.
Figure 1: Observed Symptoms in Patients
Laboratory and Radiological Findings
Mean hemoglobin was 11.3 g/dL, and leukocytosis was common. CRP was elevated in 72.7%. Sputum cultures were positive in 24.6%, mainly Streptococcus pneumoniae. Radiographs revealed unilateral infiltrates in 60.3%, bilateral infiltrates in 32.0%, and pleural effusion in 7.7%. Findings are shown in Table 3 and Figure 2.
Table 3: Summary of Laboratory Parameters at Admission (N = 300)
|
Parameter |
Mean ± SD / n (%) |
|
Hemoglobin (g/dL) |
11.3 ± 1.9 |
|
Total Leukocyte Count (/mm³) |
12,700 ± 3,420 |
|
CRP >6 mg/L |
218 (72.7%) |
|
Sputum C&S Done |
146 (48.7%) |
|
Positive Cultures |
36 (24.6% of tested) |
Figure 2: Radiological findings at the time of admission
Severity Classification
Based on clinical and radiological criteria, 36% had mild, 46% severe and 18% very severe CAP. Predictors of severity included older age, co morbidities, and bilateral infiltrates. Results are displayed in Table 4.
Table 4: CAP Severity Distribution (N = 300)
|
Severity Level |
Number of Patients |
Percentage |
|
Mild |
108 |
36.0% |
|
Severe |
138 |
46.0% |
|
Very Severe |
54 |
18.0% |
Prescription Patterns
Ceftriaxone + azithromycin were the most common regimen (43.3%), followed by cefoperazone–sulbactam + levofloxacin (21%). Intravenous dual therapy predominated in severe/very severe CAP. Adjunctive therapies included antipyretics, IV fluids, corticosteroids, and bronchodilators. Empirical therapy was used in 95% of cases, while targeted therapy was restricted to 5%. Patterns are illustrated in Table 5-6.
Table 5: Empirical vs. Targeted Antibiotic Therapy (N = 300)
|
Type of Therapy |
Number of Patients |
Percentage |
|
Empirical |
285 |
95.0% |
|
Targeted (post C&S) |
15 |
5.0% |
Table 6: Use of Adjunct Medications at Admission (N = 300)
|
Medication |
Frequency |
Percentage |
|
IV Fluids |
201 |
67.0% |
|
Corticosteroids |
93 |
31.0% |
|
Antipyretics |
251 |
83.7% |
|
Bronchodilators |
67 |
22.3% |
|
Mucolytics |
43 |
14.3% |
Changes during Hospital Stay
Regimen modifications occurred in 26% of patients, driven by culture results, clinical deterioration, or improvement. The mean antibiotic duration was 6.3 ± 1.8 days. These changes are summarized in Table 7.
Table 7: Frequency and Nature of Prescription Modifications (N = 300)
|
Reason for Modification |
Number of Cases |
Percentage of Total |
|
Culture Sensitivity Report |
14 |
4.7% |
|
Clinical Deterioration |
26 |
8.7% |
|
Clinical Improvement |
38 |
12.7% |
Correlation with Clinical Outcomes
ICU admission was required in 32% of patients, and mechanical ventilation in 16.7%. Mean hospital stay was 6.5 days, with better outcomes in patients treated per guidelines. In-hospital mortality was 4.0%, highest among those on piperacillin–tazobactam regimens. Outcomes are depicted in Table 8-10.
Table 8: Antibiotic Regimens and ICU Admission (N = 300)
|
Antibiotic Regimen |
ICU Admissions (n) |
ICU Admission Rate (%) |
|
Ceftriaxone + Azithromycin |
34 |
26.2% |
|
Cefoperazone-sulbactam + Levofloxacin |
21 |
33.3% |
|
Piperacillin-tazobactam + Azithromycin |
28 |
71.8% |
|
Ceftriaxone Monotherapy |
3 |
12.0% |
|
Other Combinations |
10 |
23.3% |
Table 9: Drug Patterns and Mechanical Ventilation Requirement (N = 300)
|
Therapy Group |
Mechanical Ventilation Cases |
Percentage of Group |
|
Dual Antibiotic + Steroid |
19 |
41.3% |
|
Dual Antibiotic Only |
15 |
23.8% |
|
Monotherapy |
3 |
12.0% |
|
Others |
13 |
30.2% |
Table 10: Mortality Association with Drug Choices (N = 300)
|
Drug Regimen |
Deaths (n) |
Mortality Rate (%) |
|
Piperacillin-tazobactam + Azithromycin |
6 |
15.4% |
|
Ceftriaxone + Azithromycin |
2 |
1.5% |
|
Cefoperazone-sulbactam + Levofloxacin |
2 |
3.2% |
|
Others |
2 |
4.7% |
Length of Hospital Stay
The mean length of hospital stay (LOS) across the entire cohort was 6.5 days (SD = 2.3). However, when stratified by prescription profile, notable differences were observed. Patients treated with regimens adherent to ICS/NCCP guidelines had a significantly shorter stay (mean = 5.4 days) compared to those managed with non-guideline-based therapy (mean = 7.2 days). Similarly, patients who received targeted therapy based on culture sensitivity had the shortest LOS (mean = 5.1 days). These findings are summarized in Table 11.
Table 11: Prescription Profiles and Length of Stay (N = 300)
|
Prescription Profile |
Mean LOS (days) |
Standard Deviation |
|
Guideline-Adherent |
5.4 |
1.8 |
|
Non-Adherent |
7.2 |
2.6 |
|
Empirical Therapy |
6.8 |
2.3 |
|
Targeted Therapy |
5.1 |
1.4 |
Adverse Drug Reactions
A total of 22 ADRs (7.3%) were reported, mainly gastrointestinal intolerance, rash, and drug-induced liver injury. Ceftriaxone, azithromycin, and levofloxacin were most frequently implicated. Results are presented in Figure 3 & 4.
Figure 3: Incidence and Type of ADRs Observed (N = 300)
Figure 4: Drugs Most Frequently Implicated in ADRs (N = 22)
Adherence to Guidelines
Overall, 62.7% of prescriptions were fully guideline-adherent, which correlated with shorter hospital stays and lower mortality. Findings are shown in Figures 5 & 6.
Figure 5: Concordance of Prescriptions with ICS/NCCP Guidelines (N = 300)
Figure 6: Outcomes in Patients Treated per vs. not per Guidelines
Physician Characteristics
Most prescriptions were issued by residents. Senior faculty demonstrated greater guideline adherence, while junior residents favored broad-spectrum use. Results are illustrated in Figures 7& 8.
Figure 7: Prescriber Qualification and Experience Profile (N = 300)
Figure 8: Association between Prescriber Attributes and Prescription Patterns
DISCUSSION
Community-acquired pneumonia (CAP) continues to be a leading cause of hospital admissions, particularly in resource-limited settings where comorbidities and delayed healthcare access contribute to disease severity. In this prospective study of 300 patients admitted with CAP, we identified important demographic, clinical, and prescribing trends that provide insights into the challenges and opportunities for optimizing patient outcomes.
The mean age of 54.2 years, with nearly two-thirds of patients being male, is consistent with prior studies from South Asia where CAP is more common in middle-aged and elderly populations. The predominance of lower socioeconomic status (61.3%) and low education levels likely contributed to late presentation and higher severity, underscoring the role of social determinants of health in CAP progression.
Classical symptoms such as cough, fever, and dyspnea were universal, while altered sensorium was more common in elderly patients. Importantly, comorbidities were present in two-thirds of the cohort, with COPD, diabetes, and hypertension being most frequent. These findings reinforce the global understanding that comorbid conditions act as amplifiers of CAP severity, with our data showing significant associations between comorbidities, bilateral infiltrates, and severe disease.
Leukocytosis and elevated CRP were common, while Streptococcus pneumoniae was the most frequently isolated pathogen in positive cultures. However, sputum culture positivity was limited (24.6%), reflecting either pre-hospital antibiotic use or diagnostic limitations. Radiological findings, particularly bilateral infiltrates, were strongly predictive of ICU admissions, highlighting their importance as early prognostic markers.
Empirical therapy was overwhelmingly favored (95%), with ceftriaxone + azithromycin being the most frequent regimen. While this aligns with global CAP recommendations, reliance on empirical therapy reflects inadequate integration of microbiological diagnostics into routine practice. Notably, piperacillin–tazobactam use was largely restricted to severe cases but correlated with higher ICU admission and mortality rates, suggesting its use as a reactive rather than anticipatory strategy.
Adjunctive therapy patterns, including corticosteroid use in one-third of patients (and nearly 60% in very severe cases), further emphasize physician reliance on supportive interventions. Although steroid use may be beneficial in selected cases, its widespread and non-standardized use highlights variability in practice.
Regimen changes occurred in one-quarter of patients, primarily due to clinical improvement or deterioration rather than culture guidance. This limited reliance on microbiological evidence highlights the need for rapid diagnostic tools to enable targeted therapy. Patients managed with guideline-adherent or culture-directed regimens had significantly shorter hospital stays and better outcomes, underlining the critical role of standardized care pathways.
ICU admissions were required in one-third of patients, and 16.7% required mechanical ventilation. Mortality was 4.0%, comparable to international inpatient CAP data, but higher than some regional outpatient-based studies. Mortality was disproportionately higher among patients on piperacillin–tazobactam regimens, likely reflecting underlying disease severity rather than drug-related risk. These findings suggest that early severity stratification and timely escalation of care may improve survival.
The ADR incidence of 7.3% was modest, with gastrointestinal intolerance, rash, and drug-induced liver injury being most frequent. Ceftriaxone, azithromycin, and levofloxacin were the most implicated drugs, consistent with their predominant use. Importantly, all ADRs were mild to moderate and reversible, underscoring that vigilant pharmacovigilance in CAP is feasible and valuable for optimizing safety in multi-drug regimens.
A key finding of this study was the strong correlation between guideline adherence and improved outcomes, including shorter hospital stay, fewer ICU admissions, and lower mortality. Only 62.7% of prescriptions were fully guideline-adherent, suggesting a major opportunity for quality improvement. Physician characteristics played a critical role, with professors and consultants demonstrating the highest adherence, while junior residents showed the greatest tendency toward broad-spectrum antibiotic use. This highlights the need for structured mentorship, regular training, and decision-support tools to guide younger prescribers.
Overall, this study underscores the complex interplay of patient factors, prescribing practices, and institutional dynamics in CAP management. Strengthening microbiological support, enforcing treatment guideline adherence, and enhancing supervision of junior prescribers represent practical steps to improve outcomes. In resource-constrained systems, such interventions could substantially reduce morbidity, mortality, and the burden of antimicrobial resistance.
CONCLUSION
This prospective observational study provides an in-depth evaluation of prescription patterns, therapeutic outcomes, and adverse drug reactions (ADRs) in patients with community-acquired pneumonia (CAP) at a tertiary care hospital. Findings highlight that CAP management is influenced by patient demographics, baseline disease severity, physician experience, and adherence to clinical guidelines.
A predominance of empirical therapy was observed, reflecting current practice but also underscoring the limited integration of microbiological diagnostics into routine care. Despite sputum cultures being performed in many patients, therapy was rarely adjusted, emphasizing the need for rapid diagnostic support to enable targeted treatment and reduce reliance on broad-spectrum regimens.
Clinical outcomes were closely linked to guideline adherence. Patients managed according to national recommendations had shorter hospital stays, reduced ICU admissions, and lower mortality. This finding reinforces the critical role of evidence-based protocols in improving prognosis, particularly in moderate-to-severe CAP cases.
The incidence of ADRs was low and manageable, yet their occurrence—especially with combination antibiotic therapy—highlights the importance of active pharmacovigilance in inpatient care where polypharmacy is common. Additionally, analysis of prescriber characteristics revealed that senior physicians adhered more consistently to guidelines, while junior residents displayed higher rates of irrational prescribing, pointing to a need for structured mentorship and supervision.
In summary, the study underscores that optimal CAP management requires more than clinical acumen; it demands strengthened diagnostic infrastructure, rational pharmacotherapy, and robust clinical governance. Prioritizing guideline adherence, enhancing stewardship, and investing in diagnostic capacity are essential to reduce morbidity and mortality from CAP, especially in resource-limited healthcare systems.
REFERENCES
Rohit Mishra, Rajendra Nath, Kamal Kumar Sawlani, Ajay Verma, Ritambhra Dwivedi, Anuj Mishra, To Evaluate Prescription Pattern, Therapeutic Outcome and Adverse Drug Reactions in Patients of Community Acquired Pneumonia Coming to Tertiary Hospital, Int. J. of Pharm. Sci., 2025, Vol 3, Issue 10, 1339-1351. https://doi.org/10.5281/zenodo.17342610
10.5281/zenodo.17342610
